Nanostructures have found application in many fields including electronics, optoelectronics and catalysis due to their unique physical properties. For instance, low dimensional nanostructures offer enhanced material characteristics due to quantum confinement effects when compared to bulk structures. In addition, these materials offer high surface to volume ratio and a high fraction of chemically similar surface sites. Nanostructures that have been successfully employed in a number of applications include nanotubes, nanowires, nanobelts, nanosheets, nanopaintbrushes and even nanodiskettes.
Nanostructures have been formed via a variety of processes and from several different materials. For instance, carbon nanotubes have been formed and used primarily in the study of thermal, optical and electrical transport phenomena in one-dimensional objects. Nanostructures such as nanowires and nanobelts have also been formed of materials including oxides of zinc, tin, indium, cadmium, magnesium and lead as well as silicon-based materials and carbides for use in a variety of in semi-conducting applications. These materials show promise in other applications also, including probe microscopy tips in sensing applications and interconnects in nanoelectronics.
Nanostructures formed of materials which display unique optical as well as electrical characteristics are being explored for use in the field of optoelectronics. Specifically, gallium-based materials such as gallium oxide and gallium nitride as well as nanomaterials of indium phosphide, gallium phosphide and cadmium sulfide have attracted a great deal of attention due to their unique electronic and luminescence properties.
Processes used to form nanostructures have included, for example, physical evaporation via vapor-liquid-solid (VLS) systems, various catalyst assisted methods, methods involving electric arc gas discharge, and pulsed laser ablation techniques. Such techniques often involve several processing steps as well as requiring the use of expensive catalysts and/or high pressure conditions. Moreover, many of these techniques cannot be accomplished without utilizing expensive and complicated equipment. In addition, such techniques have been utilized with a relatively small number of materials, and generally only used to form homogeneous nanostructures.
The breadth of application for nanostructures could be vastly increased by a simpler, less expensive method of formation. For example, a simpler method of formation could provide a route for formation of novel nanowires and nanobelts formed of materials not utilized before in such structures including novel pristine, hybrid, doped and hetero-structure nanostructures.